Interchangeable insertion type wiring device



Patented Sept. 30, 1947 OFFICE INTERCHANGEABLE INSERTION TYPE WIRING DEVICE Oscar Dorfman, New York, N. Y. Application May 8, 1944, Serial N 0. 534,661

4 Claims.

This invention relates to means for mounting an electrical wiring device in proper relation to the circuit wires of an outlet box, so that the avera e p rson, or even a housewife, an intelligent child, tenant, handyman, or other person, may safely remove a defective electrical wiring device and place a new electrical wiring device in correct position with relation to the circuit wires of the outlet box, without disturbing the connections of these wires or causing the person who does this work to be exposed to dangerous electrical wires or connections.

One of the objects of the invention is the provision of a construction for this general purpose, which will permit of the use of any switch, attachment receptacle or combination, and permit of a slip or sliding insertion of the device in working position, in'such manner that incorrect mounting is prevented, and the wiring device may then be locked in its working position in the outlet box, so that complete circuit connection is established and maintained with the electrical connections of the outlet box.

A still further object of the invention is the construction of a combination for these general purposes, which will permit of the saving of a considerable amount of wire in making the required installation, by shortening the leads of the wires to the terminals or binding posts of the unit, and to utilize these binding posts or terminals for making contact with the detachable wiring device. I

With the above and other objects in view the invention consists in certain structions, combinations, and arrangements of parts, clearly described in the following specification, as an example of one particular instance of an electrical wiring device, and fully illustrated in the accompanying drawings, in which:

Fig-1 is a vertical sectional view through an outlet box, showing the detachable combination of a single pole switch and receptacle in place therein.

Fig. 2 is a front elevation thereof, the usual finishing plate being removed.

Fig. 3 is a rear elevation of insertable unit.

Fig. 4 isa vertical sectional view, taken on line 4-4 of Fig. 1, looking. in the direction of the arrows, showing the insulating plate, which carries the terminals or binding posts.

Fig. 5 is a horizontal sectional view, taken on line 5-5 of Fig. 2, looking in the direction of the 'BII'OWS.

which illustrate one 5 designates a metal outlet box, which includes the bottom 6, and the side walls I, I, 8 and 8'. This outlet box may be equipped with the usual conductor clamps 9 new and useful conand I0, which are held in place by means of the screws 9a and Illa.

Bracket members H and I2 are arranged within the outlet box 5, and the bracket member H is formed with a holding flange Ha, which engages the marginal flange la of the side wall, and. is further formed with a seat flange lib. The flange 1a is connected to the flange Ila by means of the usual assembly machine screw.

The bracket I2 is formed with a holding flange l2a which is connected to the flange 8a of the side wall 8, by means of the usual assembly ma chine screw, and is further formed with a seat flange l2b, which is spaced from the conductor clamp l0 and the side wall 8. The seat flanges llb and I21) are disposed in the same plane and in spaced relation to each other.

An insulating plate 13, of any suitable insulating material, is snugly fitted on the seat flanges Nb and l2b, and thus wholly supported within the outlet box by the brackets H and I2. This insulating plate is formed with curved or convex edges 13c and Kid, and with two straight edges 13a and I31), which are constructed with notches or openings We and l3f, to receive the electrical conductors that enter the outlet box. Due to its shape the insulating plate is adapted to be inserted in either a standard round outlet box or a standard rectangular outlet box. The center of the insulating plate is formed with an opening Rig to receive the stud of an electrical fixture.

On the insulating plate Hi the terminals or binding posts l4, l5, l6 and I1 are mounted, through holes formed in said plate, and these posts or terminals are clamped to the plate by means of the nuts l8 and the heads IS, the latter being formed on the posts or terminals.

The free ends of the binding posts or terminals are disposed in the same general plane. In this showing four binding posts are shown, but only two or three of these may be utilized by the wiring device, which is mounted in the outlet box, and the inactive terminal or binding post will in no way interfere with the connections of the other terminals or binding posts with the wire connecting device.

The detachable wiring device includes a housing 22, in which any standard electrical connecting mechanism may be arranged. This housing or body is provided with a plurality of metal strips 23, 24 and 25. In this case three of such strips are shown, but the number required or used may equal the number of terminals or binding posts used. Two or more of such conductor strips may be thus employed.

Each conductor strip is formed with a lateral contact terminal or spring finger 26, tension being maintained on this finger by means of the spring loop 21. The finger of each strip is disposed outside of the housing 22, and the other end of the with the key 30a, and the keyway 3| is in regisposition by means of the latch button-32, pivoted strip is enclosed by the housing, and suitably connected with the wiring device parts. This housing is shown to be provided with the usual plug-in element Or receptacle 28, and the toggle lever or switch element 29. 5 The body or housing 22 is formed with grooves 30 and 3|, located in the opposite ends thereof. The groove 30 is made narrower than the groove 3|. These grooves receive the guides or keys 30a and 31a of the bracket members.

The key 30a is made narrower than the key 3 I a, so that it will fit slidably in the narrow groove or keyway 30, and the key 31a is adapted to fit only in the groove 3i, In order to insert the housing of the wiringdevice in the outlet box it 5 is therefore necessary :that the housing be positioned so that the keyway 30* is in registration tration with the key 3|a.

By properly inserting the housing of the wiring- 'device, the spring contact members or terminals '26 will be forced into electrical engagement with the contact terminals or binding posts of the insulating plate, asindicated in Fig. 5, when the spring terminals will be'placed under tension, so J that the contact will be properly maintained The housing or body 22 is retained in working to the holding flange l2a of the bracket l2, and by means of the latch button 33, which is pivoted; to the holding flange Ha of the bracket II, and this button 33 is shown to be larger than the button 32. The holding flanges of the brackets are formed with tapped holes II and I2, to receive machine screws for connecting the usual finish-35 'ing plate.

When it becomes necessary to replace the Wiring device, due to excessive wear or breakdown, all that is necessary is to remove the usual finishing plate, not shown, release the latch butt/0118,9 40 and then pull the housing out of the outlet box, without even contacting-the electrical wires or their terminals. Due to the fool-proof assembly construction it is impossible to insert a new wiring device unless the housing is correctly positionedwls with reference to the outlet box, so that the keys of the brackets will easily enter the proper keyways of the housing.

In this operation the housewife, tenant-landlord, or other person, is not required to have any- 1 sound electrical knowledge of the circuit connections, or have'skill to select and toconnect the electrical wires,and does not have to expose the fingers to the electrical terminals or binding posts.

Once the electrical wires have been properly con-,1 nected in position they may remain without further change or interference. The danger of false and loose connections being'made'by inexpericonnected to the wiring device. Experience shows that a saving of from two feet or more of wire for each installation is made, as against the prevailing practice.

Having described my invention I claim:

1. The combination with an outlet box, a wiring device, the outlet box having internal sup- 5 ports engaged by the wiring device and keyed tc the wiring device to permit of coupling between the wiring device and the outlet box in only one position, an insulating plate in the outlet box, contacts carried by the said plate and adapted to be wired to conductors terminating in the outlet box, and spring contact members carried by the wiring device and adapted to have electrical contact with the contacts of the plate when the wiring device is coupled to the outlet box, and

- adapted to be broken when the wiring device is uncoupled, without breaking the connections between the conductor wires and the contacts of the plate.

2. The combination" of an outlet box, bracket members mounted in the box and provided with flange seats arranged inopposition to each other, a plate of non-conductive material mounted on said flange seats, said brackets having keys of different Widths, contact members on said plate adapted-to be wired directly to conductor Wires terminating in the outlet box, and a wiring device having a housingprovided with keyways to receive the keys of the brackets, said keyways being of corresponding width to the keys to permit of coupling in only one position, the housin of the wiring device beingprovided with spring contacts adapted to engage the contact members of the plate.

3. -In combination, an outlet box, bracket members attached to the outer edge of the outlet box and having-lateral lugs disposed in a common plane, a plate of insulatin material mounted on the lugs, electrical wire binding posts carried by the insulating plate and disposed in spaced relation from each other, and a. service electrical circuit coupling device insertable in the box between said brackets and provided with spring contact members on the inner end thereof adapted to have electrical contact with the ends of the binding posts, said bracket members having keys of differentsize and the insulating plate and coupling device having corresponding keys engaged therewith.

4. In combination, an outlet box having opposing internal supports spaced from the sides of the box, an insulation plate mounted on-said supports and provided with a plurality of wire clamping binding posts secured thereto and adapted to be individually connected with electrical circuit wires, said supports having keys of different shapes and said insulation plate having keyways to engage the keys of the supports, and

a wire device having a bodyformed with keyways adapted to have matching engagement with the keys of the supports slidablyengaging said supports. and having, spring contact members adapted to have electrical contact with the outer ends of the binding posts.

OSCAR DORFMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,197,897 Peck Apr, 23, 1940 1,938,309 Williams Dec. 5, 1933 2,162,864 Rugg et al June 20, 1939 1,361,426 White Dec. 7, 1920 1,637,463 Benjamin Aug. 2, 1927 1,755,166 Cannon Apr, 22, 1930 1,144,781 Ravlin et al June 29, 1915 2,024,607 1 Sharp 'Dec, 17, 1935 1,768,042 Fergusson June 24, 1930 

